PROJECT SUMMARY The long-term objective of this application is to bring a trachea patch to the market to treat tracheal stenosis, or narrowing of the airway, which left untreated is a life-threatening condition that affects both young children and adults. Currently, otolaryngologists have only two major options for treating tracheal stenosis. One is a complex surgical procedure known as slide tracheoplasty that few surgeons in the country are truly qualified to perform. The other is to open the trachea wider and hold it open with a graft of rib cartilage. Both are difficult, time-consuming procedures with potential complications. We have a U.S. patent application submitted on a trachea patch biomaterial that overcomes the four major technical hurdles required to replace rib cartilage grafting: 1) mechanical integrity, 2) suturable, 3) resorbable, and 4) air-tight. There is currently nothing on the market even remotely resembling the idea of a synthetic patch for tracheal stenosis. While the academic tissue engineering community has focused primarily on regenerating an entire trachea with highly complex strategies, arguably leading to technology in search of an application, we have focused instead on identifying a specific patient indication with an unmet need and designed a technology to fill that void. Co-inventors Weatherly and Detamore have worked together for a decade, and after preliminary studies in 38 rabbits and 5 sheep, and partnering with Nanofiber Solutions in 2012, together as a team we are at an inflection point where key refinements of the technology are crucial to moving forward to a Phase II SBIR project and then onward to the clinic. The chief hypothesis is that refinement within the device realm will improve airway opening relative to the original device. We have three parallel aims to test in a single in vivo study with rabbits, each testing a different, more specific hypothesis regarding solutions to improve the technology. The Specific Aims are to test the hypotheses that each of the following will improve airway opening: 1) a faster-degrading polymer, 2) a more favorable biomaterial- cell interaction, and 3) an anti-microbial peptide. Compared to rib cartilage grafting, our trachea patch holds the following advantages: 1) No surgery to remove rib tissue, saving operating room time and cost, and eliminating potential complication/infection and morbidity at the rib site (attractive to patients and insurance companies), 2) Easy to use, as it is ?plug and play? for surgeons who perform rib cartilage grafting (attractive to surgeons), 3) No biologics or drugs are required (attractive to investors for FDA approval). For several reasons, we focus initial clinical translation on the pediatric population with laryngotracheal stenosis. In the simplest terms, our goal is to fix tracheas for kids around the world with narrowed airways to help them survive and breathe normally again.